The so-called massage generally comprises rubbing over the skin, rumpling the muscles, slapping or rapping and pressing various portions of the patient's body so as to eliminate venous congestion, to quicken arterial circulation and to stimulate metabolism of various tissues. In order to provide such massage treatments, various massager devices have been proposed.
Such devices may be divided into two types. A first type is a portable massager which is generally small in size and consequently inexpensive. However, the massage operation of the portable massager is generally poor. The second type is a chari massager which occupies a relatively large space. The operation of the chair massage is limited to the rear side of the body.
A simple portable massage device comprises a casing formed with a plurality of protrusions and a vibrating motor or electromagnetic vibrator mounted therein so as to transmit vibration to the protrusions. Such a massager can be hand held, and may be applied at any part of the body, but the massage effect is poor in comparison with that given by the professional massager.
For instance, JP-A Sho 60(1985)-49836 discloses a portable massager having a casing formed in such a way that both foot soles may be placed thereon, an electric motor mounted therein at the center, two rotatable shafts extending in opposite directions and a plurality of cams mounted on and along the shafts, and a corresponding number of protrusions projected out of the casing through holes formed therein respectively at free ends thereof, while the other ends are respectively fixed to counterpart cams so that when the motor is energized, the protrusions are alternately vertically moved to press the foot soles.
JP-A Sho 60(1985)-96256 discloses a portable massager comprises a casing, an electric motor mounted therein, a pair of disc gears respectively mounted in the casing to be rotated in opposite directions, a pair of bent shafts each respectively mounted at one end with the gears at the rotation center to be wriggingly rotated and protruded out of the casing, and a pair of balls respectively mounted on the other ends of the bent shafts and covered with flexible sleeves to be held on the casing surface so that when the casing is placed on a desired part of the user's body and the motor is energized, the wriggingly moved two balls rub the skin and rumple the muscles of the body part.
The portable massagers, however, generally can not give massage treatments over a wide area of the body at the same time.
The chair massagers are generally provided with a plurality of protrusions or balls mounted over the chair back to be vibrated, reciprocally protruded and retracted or wriggingly rotated by means of the mechanism as referred to above or similar thereto so as to give massage treatments on the waste, back, shoulders, neck and head back of the user sitting thereon all at the same time. It is, however, impossible to provide massage treatments with chair massagers at body parts such as the hand, arm, foot, leg, thigh and so on. The chair massager is further disadvantageous in that the user can be given the massage treatment only at the location where the device is positioned.
The inventor proposed a portable massager unit which is attachable to a chair, sofa, vehicle seat or the like by means of a belt so as to form the chair massager, and which has a space for an arm or foot to be inserted for taking the massage treatment in JP-A Sho 63(1988)-38458 early opened on Feb. 29, 1988. This massager unit comprises a box-like casing of which top and one end is open; a plate member extending along the open top thereof and pivotally mounted at the center on the casing side walls; and an electric motor mounted in the casing so as to leave the space referred to above open at the above one end so that an output shaft thereof is drivingly connected with one end of the plate member through a crank mechanism to swingly drive the plate member. On the outer surface of the plate member is arranged a plurality of protrusions, each preferably made of an elastic material or adhesively applied with a elastic material sheet formed with a plurality of protrusions suitable for massage of the user's body at the rear side from the waist up to the head. The plate member is arranged with a plurality of protrusions or adhesively applied with an elastic material sheet formed with protrusions at the inner surface so as to give the massage treatment on an arm or leg inserted in the above space of the casing.
This massager unit is, however, still disadvantageous in that the protrusions arranged on the straight or planar and rigid plate member pivoted at the center thereof for swinging can not suitably fit on the corresponding portions of the user's body at the rear side which is usually more or less bent. Further, the massage effect is generally a too simple slapping or rapping, too strong at the portions near to the opposite ends of the plate member, and too weak at the center portion. In addition, the massage effect is too strong on leg or thigh while too weak on the arm thinner, and is difficult to be given on the hand and foot.